Thin film battery cell components, such as the anode, cathode and electrolyte, can be sensitive to exposure to the surrounding external environment (e.g., air, oxygen, carbon monoxide, carbon dioxide, nitrogen, moisture and organic solvents). Protective packaging for the battery cell is provided to reduce or eliminate exposure of the battery components to the external environment. For example, a multi-layer film can be sealed around the periphery of the battery cell to serve as protective packaging. Thin film batteries can also have one or more current collector tabs protruding from the battery cell to allow for external electrical contact with the device being powered. These protruding tabs must necessarily extend through the seal in the packaging material. However, the tabs protruding through the seal may compromise the integrity of the seal thereby reducing battery life. In addition, the packaging material may include a metal foil layer to reduce the moisture vapor transmission rate of the packaging material. The edge of the metal layer adjacent the tabs can contact the surface of the tab thereby creating a short.
Accordingly, there still exists a need for improved methods of packaging thin film batteries having one or more protruding tabs which allow for the tabs to extend through the seal in the packaging material without compromising the seal or creating a short between the tabs and metal foil in the packaging material.